Picker drive mechanism



Dec 3, 1968 s. c. DANGEL Em. s,4 ,0 3- I PICKER DRIVE MECHANISM Filed May 20, 1966 2 Sheets-Sheet l Dec. 3, 1968 5 DANGEL ETAL 3,414,023

PICKER DRIVE MECHANISM 2 Sheets-Sheet 2 Filed May 20, 1966 K m M W W. m m w M. J W4 mu! IIJ 7U 1 9 V a g j H 0 w J u I M 0 I 4 kw 0 J 0 ya 0 a \m. 1 m w ,2 1 w United States Patent PICKER DRIVE MECHANISM Stephen C. Dangel, 329 Park St., Boston, Mass. 02132, and George B. Kirby Meacham, 414 S. Crest Road, Chattanooga, Tenn. 37404 Filed May 20, 1966, Ser. No. 551,770 20 Claims. (Cl. 139-145) ABSTRACT OF THE DISCLOSURE Picker drive mechanism for a power-driven weaving loom in which, when the loom is in normal operation, energy is accumulated during the nonpicking portion of each cycle of the picker cam and delivered to the picker at the inception of the picking stroke of the picker thereby to accelerate the picker, but which does not so accumulate energy when the loom is being operated by hand.

The present invention relates to drive mechanism for throwing or picking a weft carrier, such as a shuttle, gripper, or other thrown element, in a power-driven loom.

In a conventional loom the sudden motion required to throw the shuttle produces a very uneven consumption of energy during a cycle, produces high stresses, and constitutes a practical limitation on loom speed because of tendency to cause wear of the pick ca-m at high speed.

Objects of the present invention are to reduce the detrimental effects which have accompanied the required sudden motion, and in particular an object is to permit increase in loom speed.

Generally, the invention involves introduction of an energy storing means in the pick motion, and certain related features whereby this can be done advantageously.

Other objects and advantages of the invention will be apparent from this specification and its accompanying drawings, in Which drawings:

FIG. 1 is a fragmentary view in the nature of a side elevation partly in vertical section showing the left hand pick shaft and pick cam of a power-driven loom having picker drive mechanism of the present invention applied thereto;

FIG. 2 is a plan view of some parts shown in FIG. 1;

FIG. 3 is a diagrammatic elevation taken at right angles to FIG. 1 showing hydraulic mechanism for recovering energy from the weft carrier and picker stick and for returning the recovered energy to the picker drive mechanism;

FIG. 4 is a detail view from the same point of view as FIG. 1, showing the application of a spring to the linkage of FIG. 1 to assure return of the pick shaft, pick arm, and lug strap before the shuttle is boxed, this spring being intended for use only with the hydraulic energy recovery system of FIG. 3;

FIG. 5 is a fragmentary view mainly in vertical section of an alternate form of energy storing means for the picker drive mechanism;

FIG. 6 is a diagrammatic view in the nature of a plan of parts of the device of FIG. 5, some parts being omitted.

Referring to FIGS. 1 and 2, there is shown a picking system for a loom comprising the usual pick shaft 10, broken away in FIG. 1, carrying the usual pick arm 11, engaging at its free end the usual lug strap 12.

A power-driven pick cam shaft 15, rotating in the clockwise direction, FIG. 1, carries a pick cam indicated generally at 16. Cam 16 has a groove 17 on the side facing the observer in FIG. 1, in which groove a cam follower 18, FIG. 2, is adapted to run. The inner peripheral wall W of groove 17 may have a cam shape such as generally 3,414,023 Patented Dec. 3, 1968 employed in pick cams in which the follower follows the outer periphery of a nongrooved cam, this wall having a fast rise between C and A in FIG. 1, followed by a slow fall through the region from A to B, followed by dwell in the region from B to C.

The drive of the pick motion, according to the present invention, is, however, primarily under the control of the outer wall W1 of groove 17, against which the cam follower roller is normally urged. This outer wall W1 of the groove has the same cam pattern as the inner wall W with a rapid rise from C to A, a slow fall from A to B and a dwell from B to C.

The follower roller 18 is carried by a swinging arm 20, pivoted at 21. The left end of arm 20 in FIGS. 1 and 2, in rising with the rise of the follower roller 18, lifts a lug 23 which is bolted to the pick shaft 10 and thus turns the shaft.

The axis of the pivot 21 of the arm 20 intersects the axis of the pick shaft 10. The contact faces of the arm 20 and lug 23 are shaped in the form of tapered involutes with the center of taper at the intercept of the axes of the pivot 21 and the pick shaft 10. This results in rolling contact such as is obtained between the teeth of involute gears.

The energy storing means, which receives energy from the pick cam shaft 10 during the slow fall of the outer wall W1 of cam groove 17, stores energy preferably in a spring, that is to say gradually compresses the spring and so charges it with energy.

The energy thus stored up in the spring or equivalent storing device and which is stored up during that portion of the revolution of the picker cam 16 which follows immediately after the picker has completed its shuttle picking stroke is suddenly released an instant before the cam starts the picker on its next active stroke in such a way as to assist the cam in suddenly accelerating the picker and thus effectively reduces the wear on the cam and makes it possible to increase the speed of the loom.

However, it is necessary, at times, for the loom operator to disconnect the power drive and turn the loom over by hand, for example, to make repairs to the shed or mechanism, or to make adjustments. In turning the loom by hand the picker cam, of course, is turned and if the loom be equipped with energy storing means, as above suggested, such energy would be stored up during the hand operation and eventually the rotation of the cam would release that energy with the result that the picker would drive the shuttle across the loom. This would be very dangerous to the operator. It may be noted here that in the ordinary high speed power-driven loom the drive from the motor comprises a hand controlled clutch, here diagmmatically indicated at CL (FIG. 1), so that the loom may be stopped when desired by the manual actuation of a shipper handle S.

In accordance with the present invention provision is made whereby such accidental operation of the picker, when the loom is operating at less than normal speed, is prevented. The arrangement, whereby this result is obtain ed, is shown, in accordance with one embodiment, in FIGS. 1 and 2 of the drawings, wherein the energy storing means is shown as a compression spring35.

6 Thus, as indicatd in FIG. 1, a rigid, tubular connecting member or sleeve 30 is pivotally connected at 31 to the lever 20 and is rigidly secured at its lowerend to' a spring housing comprising a cap-like top member. or flange .33 which rests upon the upper convolution of a compression spring 35. The spring housing also comprises a. bottom member 37 on which the lower convolution of the spring is supported. The housing also comprises bolts 39, which passloosely through holes in the flanges 33 and 37, the effective lengths of which may be adjusted by nuts N; The flange 37 is here shown as integral with an inverted cup 38 whose peripheral Wall is housed within the spring 35, and whose top wall D is fixed, by a pin, to a rod 45, hereinafter referred to as a piston rod, whose upper portion slides within the tubular connecting member or sleeve 30. The spring may, if desired, be precompressed to a desired extent, thereby to insure a more powerful pick, by reducing the effective length of the bolts 39 to tightening the nuts N at their ends. It may be noted at this point that were not the flange 37, on which the spring rests, supported in some manner, the mere up and down motion of the sleeve 30 and flange 33 would have no effect upon the spring.

In the embodiment of FIGS. 1 and 2 the spring is made ineffective during periods while the loom is not driven by the motor by means of a dashpot comprising a cylinder 40 closed at opposite ends and which is permanently anchored at its lower end, so that it cannot move vertically, by a pin which connects it to a fixed part of the loom frame. Within the cylinder there is a piston 41, with suitable cup type packing 42 between the piston and cylinder. The cup-type packing constitutes a one-way valve, making a tight seal with the cylinder wall on the down-stroke and a loose fit with the cylinder on the upstroke. Other types of one-way valves could be employed. The piston rod 45 which carries the piston is slidable in the sleeve 30 and fastened at 47 to the top of sleeve 38. The dashpot is full of fluid and there is restricted flow from one side to the other of the piston through a small orifice 48. Thus the spring 35 is, in effect, supported by the piston of the dashpot. When the loom is running at its normal high speed, being driven by its motor, the cyclic motions imparted to the cam follower 18 and hence to the spring housing 33, 39, 37 and are so fast relatively to the dashpot cylinder 40, that very little fluid can flow through the passage 48 during any one cycle, and the piston 41 can move very little from the position corresponding to that at which the cam follower roller is at its high point and the spring 35 is least compressed. Thus, nearly all of the fall of the outer wall of the cam groove 17 is reflected in compression of the spring 35. In other words, there can be only very little collapse of the dashpot during fast cyclic motion, and the piston forms a nearly rigid support for the energy storing spring.

011 the other hand, in a slow turning over the loom by hand the dash pot permits the piston to move fairly freely in the cylinder and permits the lower end of the spring to be as far away from the upper end of the spring as permitted by the bolts 39, so that the spring does not store appreciable energy as the result of this slow turning over, and accordingly does not transmit a sudden blow to the shuttle when the time for a pick is reached. The picker stick will merely have a gentle slow movement, corresponding to the slow turning over of the loom.

The spring will usually be somewhat charged beyond its precompressed condition at the time when the loom comes to a stop. However, the dashpot will very quickly permit discharge of energy from the spring so as to render it ineffective. and it will be apparent that this discharge is not through the pick shaft. Thus the pick motion is prevented from being left in a condition which would permit a forceful pick upon turning the loom over by hand.

If the running conditions of the loom are such that the energy stored in the spring may not alone be sufficient to effect picking in proper time, there can be a combined action at the time of picking by energy supplied by the spring and by positive camming action by the inner surface of the cam groove 17 which will effect picking at the proper time and with the desire-d suddenness. To the extent that energy is stored in the spring during the nonpicking part of the cam cycle, and is discharged to aid in the picking, the energy consumption curve of the loom is made more even, the running of the loom is made smoother and the action upon the cam is made less severe.

Loom speed is limited basically by the rate of wear of the pick cam which can be tolerated. By lessening of severity of the action on the pick cam, through this invention, it becomes practicable to increase loom speed.

It has been mentioned that in normal running at high speed there will be a slight collapse of the dashpot with fall of the cam follower. The total follower lift will be greater, by the amount of this dashpot collapsedistance, than the length of the part of the lift during which the energy storage spring assists the picking action.

It is common practice to provide a device for checking the inward or picking stroke of the picker stick. It is also common practice to allow the picker stick to be returned to picking position by the blow imparted to it by the boxing shuttle and to provide for checking this return movement of the picker stick in order to stop the shuttle with less tendency for it to rebound. These checking expedients involve a considerable loss of energy.

The present invention preferably provides for conserving and putting int-o the energy storing means, for example, a spring, a considerable part of the energy which is available at the picker stick but which is not actually used in throwing the shuttle. The mechanism for accomplishing this is shown in FIGS. 3 and 4. This mechanism comprises a spring 60 so arranged as to tend to hold the lug 23 firmly against the arm 20 so that the pick shaft, pick arm and lug strap will follow the return movement of the arm 20 and cam follower 18. This spring, as here shown, is a tension spring (FIG. 4) connecting the lug 23 and the upper flange 33 (FIG. 1) which is attached to the sleeve 30, which in turn is connected to arm 20. This spring is .not used in cases where energy recovery from the picker stick is not desired, because in such cases some return movement of the lug strap, pick arm and pick shaft by direct flow of energy from the picker stick to the lug strap is useful as a means for dissipating energy and preventing snapping off of the picker stick.

In FIG. 3 the lower portion of a picker stick is shown as mounted in the usual parallel assembly 66 carried by the rocker shaft 67. A hydraulic cylinder 68 is swiveled at its right end by a ball and socket connection 69 to an upright of the frame of the loom. A rod 70, slidable along the axis of the cylinder extends out of the left end of the cylinder to another ball and socket connection 72 on the picker stick. The picker stick operates this rod by the ball joint 72.

Within the cylinder, pistons 76 and 77 are provided with cup packing 76a and 77a engaging the cylinder wall, and directed away from the ends of the cylinder toward the middle of the cylinder, and adapted to allow fluid to pass from an end portion of the cylinder into the middle but to substantially prevent passage of fluid outwardly from between the two pistons. The pistons are movable relatively to the rod 70 and are yieldingly pressed against stop rings 80 and 81 by a compression spring 83. A stop ring 85 fast on the rod 70 is adapted to strike the piston 76 on right-hand movement of the rod after the picking part of the cycle of the stick and force this piston toward the middle of the cylinder, and a similar stop ring 86 on the rod is adapted to strike the piston 77 on the left-hand movement of the rod during return of the picker stick and force this piston toward the middle of the cylinder. This latter action occurs as the boxing shuttle returns the picker stick. The pump comprised of the cylinder 68 and its pistons 76 and 77 thus imposes no load on the picker stick while the latter is picking, but abstracts energy from the stick in checking the final inward and final outward movements of the stick, which energy is customarily dissipated without being used. By connections now to be described this energy is returned into the drive system.

A conduit 90 provided with a check valve 91 is adapted to convey fluid from the middle of the cylinder 68 to the lower part of the cylinder 40 of the dashpot previously described. Conduit 92 is adapted to convey fluid from the upper part of the cylinder 40 of the dashpot to a reservoir (not shown) and conduits 93 and 94, provided with check valves 95 and 96, are adapted to convey fluid from this same reservoir to respective end portions of the hydraulic cylinder 68. By means of the reservoir both the dashpot and hydraulic cylinder are maintained full of fluid at all times.

Each time the picker stick approaches the inner end of its stroke after the picking part of the cycle of the stick the left hand piston 76 is actuated to force fluid into the dashpot, and similarly each time the picker stick receives the blow of the boxing shuttle the right-hand piston 77 forces fluid into the dashpot.

These increments of fluid urge the dashpot piston upwardly, tending to stress the energy storage spring 35, and thereby relieve the pick cam of some of its work.

As in the embodiment of FIGS. 1 and 2, upon stopping of normal driving of the loom, the dashpot permits the energy storage spring to become ineffective.

In the device of FIGS. 1 to 4 the energy storage means is rendered ineffective when normal drive of the pick cam is interrupted, for as will be apparent from the above, energy can be discharged from the spring without being transmitted to the pick shaft when the piston 41 is moved only slowly and as a result is not sufficiently supported against collapse. The energy storage spring can also be rendered ineffective by unlatching a latch 104 which supports the spring during normal drive as will be described in connection with FIGS. 5 and 6.

In the device of FIGS. 5 and 6 the energy storage spring 35 is supported by the lower flange 37 of a sleeve 38 as in FIG. 1, and sleeve 38 is fastened by a pin to a rod 45a corresponding in position to the piston rod 45 of FIG. 1, but having no piston, this rod 4511 being slidable in sleeve 30. The rod 45a is normally supported by a pin whose opposite end projects therefrom as shown at 101 and 102, the laterally extending parts of the pin resting on the upper edge of a rotatable latch sleeve 104. Sleeve 104 is supported by a fixed part K1 of the loom frame and rotatably mountedin a ball and socket joint 106, and may be rotated by an arm 108 fixed to the lower part of the sleeve and adapted to be turned by connections to the shipper handle S (FIG. 1).

The sleeve 104 is provided with diametrically opposed vertical slots 109, one of which is shown in FIG. 5, so that by turning the sleeve the projecting parts 101, 102 of the pin may drop into the slots 109 and the rod 45a allowed to move down, thus unloading the spring. This occurs when the shipper handle is moved to stop the loom, and prevents the spring from being effective to cause a pick.

Thus in FIGS. 5 and 6 the energy storage spring is normally supported by a latch comprising the pin and the rotatable sleeve 104, but this latch is released and the spring unloaded when the pick cam is disconnected from its normal drive.

A rod 110, connecting the shipper lever 108 (FIG. 5) to the shipper handle S, is slidably mounted in a pin 111 which is swiveled in the outer forked end (FIG. 5 of the lever) 108, and carries a stop collar 113 adapted to bear against the arm and move it positively in the clockwise direction. This occurs when the shipper handle is moved to stop the loom, and the rod 45a is thereby allowed to drop, the pin portions 101 and 102 entering into the slots 109.

In the other direction, that is, upon starting the loom, rod 110 operates the lever 108 by means of a stop ring 115 and a compression spring 116, on rod 110 (FIG. 6) thus stressing this spring while the pin on rod 45a is in the slots 109. Thus the energy storage spring 35 will not contribute to the first pick, but at the first pick the pick cam will raise the sleeve 30, permitting the sleeve 38 and rod 45a to rise until the pin carried by rod 45a leaves the slots 109, whereupon the spring 116 (FIG. 6) will move arm 108 so as to turn the "sleeve 104 in the counterclock- Wise direction in FIG. 6, resetting the device for normal running.

In the device of FIGS. 5 and 6 the upper and lower flanges 33 and 37 may be constrained by bolts 39 for the purpose of precompressing the spring as in the device of FIG. 1. The energy represented by this precompression is not released by the release mechanism of either FIG. 1 or FIG. 5, but it can be seen that this energy represented by the precornpression would not in any event be transmitted to the picker mechanism.

It will thus be observed that the cam 16, the cam follower 18, the pin 31, the tubular member 30 and the flange 33 constitute means for transmitting energy from the power-driven shaft 15 to the energy-storing spring 35; that the flange 33, the tubular member 30 and the pin 31 also constitute elements of means, including a pivotally supported arm 20 and a lug 23, for transmitting energy from the energy-storing means to the picker shaft 10, and that means for transmitting energy from the energy-storing spring 35, without transmission thereof to the picker shaft 10, when the power-driven shaft is not subject to normal drive, comprises a collapsible device including the flange 37, the sleeve 38, the piston rod 45, the piston 41 with its restricted part 48 and the dashpot cylinder 40 permanently anchored at its end to a fixed part K1 of the loom from the collapsible device inherently opposing shortening of the spring when the loom is running under power at normal speed.

Further, it will be noted that the power-driven shaft 15 receives the driving force from a motor in customary fashion through a conventional clutch indicated at CL (FIG. 1) which is controlled by a shipper handle S (FIGS. 1 and 6) so that the power drive may be discontinued at will.

We claim:

1. In a loom including picking means for a weft carrier, a pick shaft, a power driven shaft, energy storing means, means for transmitting energy from the power driven shaft to the energy storing means and for transmitting energy from the energy storing means to the pick shaft, and apparatus for discharging energy from the energy storing means without transmission thereof to the pick shaft when said power driven shaft is not subject to normal drive.

2. The structure as set forth in claim 1 wherein the energy storing means is a spring having one end portion connected to the means for transmitting energy, and the apparatus comprises collapsible means for restraining the other end portion of the spring.

3. The structure as set forth in claim 2 in which the collapsible means is a dashpot.

4. The structure as set forth in claim 2 including latch means adapted to prevent collapse of said collapsible means, said latch means being releasable by a loomcontrolling part.

5. A power loom having picking means for a weft carrier including a pick shaft, an energy storing means comprising a spring, rotary cam means, means for connecting said cam means to and disconnecting said cam means from a source of power, means for connecting one end of said spring to said cam means and to the pick shaft, means for restraining the other end of the spring to permit the spring to be charged with energy by the cam means and to discharge energy to the pick shaft under control of the cam means with said restraining means being essentially ineffective when the cam means is disconnected from the source of power.

6. A loom as claimed in claim 5 in which the restraining means comprises a dashpot.

7. A loom as claimed in claim 5 in which the restraining means comprises a latch, the loom including an interconnection between the latch and the connecting and disconnecting means.

8. In a loom including picking means for a weft carrier, a pick motion including cam means having two cam surfaces, cam follower means, the two cam surfaces acting oppositely on the follower means, a pick shaft, energy storing means including a moveable part, and connections adapted to transmit driving force from the moveable part of said energy storing means and from the follower means to the pick shaft during the picking stroke of said shaft.

9. The structure as set forth in claim 8, including means for discharging energy from the energy storing means without transmission thereof to the pick shaft when the cam means is not subjected to normal drive.

10. Loom pick motion comprising a pick shaft, an energy-storing spring connected to drive the pick shaft, means for charging the spring with energy, weft carrier picking means driven by the pick shaft, means for recovering energy from the picking means and means for transmitting such recovered energy to the spring.

11. Loom pick motion as claimed in claim 10, in which the means for recovering energy comprises a fluid pump connected to be driven by the picking means in a nonpicking part of the cycle thereof.

12. Loom pick motion as claimed in claim 11 in which the means for transmitting recovered energy to the spring includes a dashpot restraining one end of the spring and a fluid connection from the pumpto the dashpot.

13. In a loom having a picking system including a pick member for operating a picking mechanism, a driven member, and apparatus for imparting movement to the pick member from the driven member, said apparatus comprising:

energy storage means,

means for transmitting energy from the driven member to the energy storage means and for transmitting energy from the energy storage means to the pick member, and

means for discharging energy from the energy storage means without transmission thereof to the pick member when said driven member is not subject to normal drive.

14. The structure as set forth in claim 13 wherein said energy storage means comprises a Spring.

15. The structure as set forth in claim 13 wherein said means for transmitting energy comprises cam means having at least one cam surface and a cam follower for the cam surface.

16. The structure as set forth in claim 13 wherein the means for discharging energy comprises a dashpot.

17. The structure as set forth in claim 13 wherein said means for discharging energy comprises a mechanical type latch together with means for releasing the latch when the driven member is not subject to normal drive. 18. The structure as set forth in claim 13 wherein the energy storage means comprises a spring, and

the means for transmitting energy comprises cam means having two cam surfaces and a cam follower for the cam surfaces with the two cam surfaces being disposed to act in opposed directions relative to the cam follower. 1.9. The structure as set forth in claim 13 wherein the energy storage means comprises a spring,

the means for transmitting energy comprises cam means having two cam surfaces and a cam follower for the cam surfaces with the two cam surfaces being disposed to act in opposed directions relative to the cam follower, and the means for discharging energy comprises a dashpot. 20. The structure as set forth in claim 13 wherein the energy storage means comprises a spring,

the means for transmitting energy comprises cam means having two cam surfaces and a cam follower for the cam surfaces with the two cam surfaces being disposed to act in opposed directions relative to the cam follower, and the means for discharging energy comprises a mechanical type latch together with means for releasing the latch when the driven member is not subject to normal drive.

References Cited UNITED STATES PATENTS 137,798 4/1873 Ross 139145 1,175,772 3/1916 Kelley 139145 2,160,339 5/1939 Moessinger 139145 2,452,380 10/1948 Kronoif et a1. 1391 2,621,680 12/1952 Vincent et a1 139-147 3,227,186 1/1966 Baugham et al 139156 FOREIGN PATENTS 18,786 1894 Great Britain. 218,733 7/1924 Great Britain.

MERVIN STEIN, Primary Examiner.

I. KEE CHI, Assistant Examiner. 

